The present invention relates to a method of manufacturing a semiconductor device.
Referring to FIGS. 12A and 12B, a semiconductor device of known types will be described. FIG. 12A is a cross-sectional view of a semiconductor device 100, and FIG. 12B is a bottom view thereof.
Referring to FIG. 12A, electrodes 104 made of copper foil or the like are formed on the top face of a supporting substrate 101 made of glass epoxy or the like. Further, on the back of the supporting substrate 101, back electrodes 105 are formed and connected to the electrodes 104 through via-holes 106. Moreover, the electrodes 104 and the back electrodes 105 are covered by plated films 109.
A semiconductor element 102 as a semiconductor element is firmly fixed on the supporting substrate 101 and connected to the electrodes 104 using fine metallic wires 103. Further, sealing resin 107 is formed such that the sealing resin 107 covers the semiconductor element 102.
Referring to FIG. 12B, on the back of the supporting substrate 101, the back electrodes 105 are provided in two lines parallel to the periphery of the supporting substrate 101.
In the aforementioned semiconductor device 100, since the supporting substrate 101 has been adopted, the thinning and miniaturization thereof have limitations. Further, thermal stresses have been generated by the change in the temperature in usage situations, and the reliability of connection paths from the back electrodes 105 to the electrodes 104 has had a problem. Moreover, the supporting substrate 101 is necessary to adhere the electrodes 104 and the back electrodes 105 to each other in a manufacturing process, and it has been difficult to manufacture a semiconductor device without this. Furthermore, since the supporting substrate 101 has the role of absorbing thermal stresses, it has been difficult to construct a semiconductor device without the supporting substrate 101.